Rehabilitation following an orthopaedic injury or neurological disturbance is often an essential phase of the return to normal or near-normal functioning. The aim of the research proposed here is to provide an innovative device for the evaluation and training of the neuro-musculo-skeletal system which incorporates state-of-the-art computer and robotic technology. The proposed system would have capabilities currently not available on other such devices, including the ability to allow three-dimensional movements at two adjacent joints on the human body under controlled conditions. The device could measure strength under a variety of movement modes, provide resistance to movement for rehabilitation and strength training, or manipulate a passive limb. Isokinetic, isotonic, or varying resistance would be possible with muscles undergoing concentric, eccentric, or isometric contractions. Desired movement paths would be learned by the robotic system in a learn mode, and subsequent movements could be constrained to reproduce the learned path. Redundant safety features would insure safe operation, and menu driven data acquisition and analysis software would make the system easy and efficient to use. Potential uses for the robotic device include physical rehabilitation and testing in clinical applications and strength training and testing in sports medicine, scientific and athletic training facilities.